The present invention is related to the field of diagnostics for robotic mechanisms operating within an automated storage library.
As automated storage libraries have become larger and more complex, their designs have evolved from a single robotic arm performing all data cartridge manipulations to multiple independent robots operating on several data cartridges simultaneously. This ability to manipulate several data cartridges simultaneously has increased the throughput of the automated storage libraries. While one independent robot is busy transferring one data cartridge from a storage cell to a media drive for mounting, a second independent robot can be transferring another data cartridge to an excess port, while a third independent robot may be conducting an inventory of the automated storage library.
Having multiple independent robots in operation within an automated storage library adds to the complexity of detecting and isolating failures of the individual robots. Each independent robot typically has some form of diagnostics built into its electrical, mechanical and optical circuits. This built-in diagnostic capability generally allows the robots to detect the loss of a major function, and may allow for fault isolation down to a single component or a group of components. Increasing the complexity of the built in diagnostics allows for more faults to be detected and bulk isolation to be more accurate. Built-in diagnostics, however, has practical limitations when applied to the robots. Increased diagnostics complexity adds to the overall cost, weight, volume and power consumption of each robot while reducing the mean time between failures. Furthermore, several common failure modes, such as the loss of electrical power, can leave the robot incapable of testing itself.
What is desired is a design approach and method of operation that allocates part of the diagnostic capabilities away from the independent robots and places it elsewhere within the automated storage library. Such an approach would help to minimize the cost of obtaining and operating the independent robots while still maintaining an acceptable level of fault detection and isolation within the automated storage library.
The present invention is a method of operating an automated storage library, the automated storage library structure, and the structure of independent robots operating within the automated storage library. The present invention divides a diagnostic capability for the independent robots between the robots themselves and a diagnostic center associated with the automated storage library. In operation, each robot is capable of mating itself with the diagnostic center to facilitate testing of the robot. Mating between the diagnostic center and an individual robot is performed through a pair of connectors. A main connector is electrically interfaced to the diagnostics center and is positioned within the automated storage library where it can be accessed by the robots. Each robot carries a test connector that is interfaced to the robot""s electronics. Test connector is positioned on the robot""s chassis and oriented with respect to the main connector such that the two connectors mate when the robot is approximately at a predetermined position adjacent to the main connector.
Automated storage libraries having multiple independent robots can use a second robot to assist in testing a first robot. Assistance by the second robot may include physically moving the first robot to the main connector, providing an alternate communication path between the first robot and the diagnostics center, and performing diagnostic tests on the first robot by the second robot itself. In order to support communications through the second robot or testing by the second robot, each robot may include a secondary connector mounted on the chassis. The secondary connector is also electrically interfaced to the robot""s electronics and is oriented to mate with the test connector of another robot as if it were the main connector.
A switching matrix may be provided on each robot to assist in routing of test signals, commands and information between the robot""s electronics, test connector and secondary connector. The switching matrix may be as simple as one-to-N multiplexer that allows for fan in/out between the test connector""s conductors and the robots""s electronics. More complex switching matrices may include cross point switches which allow individual signals to be selectively connected between the test connector, the secondary connector and the electronics.
The diagnostics center includes a variety of test hardware and software that can be interfaced to the robot under tests through the main connector. Optical inspection, stimulation, and optical sensing may also be provided at the diagnostics center to aid in testing the robot.
Accordingly, it is an object of the present invention to provide an automated storage library having at least one robot therein, and method of operation wherein at least part of the diagnostic testing of the robot is performed from a diagnostics center to which the robot can mate.
Yet another object of the present invention is to provide a robot for use in the automated storage library wherein the robot is capable of mating with the diagnostics center to facilitate testing of the robot.
Yet another object of the present invention is to provide a method of operating an automated storage library having multiple robots wherein a second robot supports testing of a first robot.